Q: If the hemoglobin values of a population of 2000 patients follows normal distribution and is found to have a mean of 13.5 g/dL, what proportion of the population would have value more than 13.5 g/dL?

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  1)  0.1

  2)  0.25

  3)  0.75

  4)  0.5

Answer: 0.5

The mean divides the sample into 50% below and 50% above. In the Question, mean=13.5 g/dL. Hence, sample above 13.5g/dL will be 50% (or 0.5 proportion).